TIG for spotwelding?
 

While cleaning up a very little I ran across the tig torch setup for my 3n1 machine that does tig stick and plasma. I have only used the plasma since buying this machine in 2010. I have a huge 230 volt welder that I have used a very long time, but got to wondering about the use of tig in spot welding and welding in patches. The torch has a button on the torch so there is no foot pedal[ I think that is a compliant for working in a car] So my question is what Tugnsten and what rod do I need? Also will my 75% 25% Argon mix work I'd hate to lease a new bottle just to try this TIG thing out. Thanks

Re: TIG for spotwelding?
 

To be clear my 230 volt machine is a MIG welder that I have used to put in my patches and spot new panels where needed

Re: TIG for spotwelding?
 

Not exactly sure what you're asking, but you should use pure argon and not the 75//25 mix for TIG. Somewhere on the web i saw a demonstration of what happens when you use a mix gas with a TIG and it was less than ideal and I suspect with thin sheet metal it'd be even worse.

I'd look for a rod and tungsten with a diameter about the same thickness as what your welding. A thumb control for sheet metal would be a challenge for me, but maybe you're more familiar with it than I am.

I prefer to weld in my patches with gas or TIG. Just my opinion, but spending the extra time to get a near perfect fit and using little to no filler rod saves a lot of time in grinding and stretching the metal back out after welding. The technique I was taught was to tack it about every inch or so, then go back and weld it an inch or two at a time, and each time you finish a weld, hammer and dolly the weld while it is hot.. After the metal has cooled to near room temp and you've realigned any mismatch, do it again in an opposite side of the patch. When you're done, turn off the lights and hold a light to the backside a and look for pinholes.

Re: TIG for spotwelding?
 

And for making plug welds, a MIG is just a whole lot faster. I wouldn't use a TIG unless I easy worried about splatter or it had to be super nice looking

Re: TIG for spotwelding?
 

TIG is always superior if you have the skills and right equipment. MIG is faster cheaper, and requires less skill.

Re: TIG for spotwelding?
 

TIGs work fine for spot welding, since you can heat without filler metal. For things like welding on a pinch or re-welding a cut spot weld, they are great.

Re: TIG for spotwelding?
 

That is kinda what I was wondering. Like doing rockers and such where there are real spot welds to make

Re: TIG for spotwelding?
 

I have to say, I have never touched a TIG. But I use a torch and it's very similar in use. The TIG and the MIG (or in my case the Torch and the MIG) are two completely different animals for different things. You can use them both to do the same stuff, but one is much better at certain things than the other.

Butt welding a long seam in sheetmetal, the TIG (torch) is FAR superior for fine work. Where as plug welds on floor pans the MIG blows away the TIG (torch).

So honestly, both would be cool. But if you have to have one, just one, for the average guy I say the MIG hands down.

GIT-R-DUN!

Brian

Re: TIG for spotwelding?
 

Using the TIG for tacking panels together, note the minimal/non-existant HAZ


https://www.youtube.com/watch?v=aTqQJoecqCw

Re: TIG for spotwelding?
 

For filler rod plain ole MIG wire .023 works great.
My tungsten is the scary thoriated version that is .040 in diameter or you could go with 1/16.

I do remember a person on metal meet using a TIG to do factory like spot/plug welds. With practice they looked OE in appearance and passed the destructive test.
I've also seen guys do spot/plug welds with a MIG and then come back with a TIG and "contour" the weld with the torch to give that OE look.

Re: TIG for spotwelding?
 

I use TIG as much as I can. Way easier to clean up after than MIG.

Rule of thumb: Match tungsten, rod, and metal as a starting point.

If you have DC lift arc tig, it doesn't like the .040 tungsten. It sticks while trying to start the arc. But with HF start, .040 makes a nice tight HAZ! So with lift arc, I would start with a sharp 1/16" tungsten.

No filler will leave a small undercut. .023" wire vaporizes too quickly before dipping into the puddle. .035" filler is just about right. .045" wire is too big and will cool the puddle, and leave a lot more to grind off.

Pedal will be way easier than torch switch. You need to back off the heat as you go with sheet metal.

Great video on TIG welding patches:
https://www.youtube.com/watch?v=NZ_S-7ZSvHk

Cheap tungsten grinder:
https://www.harborfreight.com/multip...ner-99823.html